{"paper":{"title":"Analytic Inverse Design of Temporal Metamaterials via Space-Time Duality","license":"http://creativecommons.org/licenses/by/4.0/","headline":"Prescribing rational reflection and transmission responses produces closed-form time-varying refractive index profiles for temporal metamaterials.","cross_cats":["cond-mat.mtrl-sci"],"primary_cat":"physics.optics","authors_text":"Carlo Rizza, Giuseppe Castaldi, Marino Coppolaro, Massimo Moccia, Nader Engheta, Vincenzo Galdi","submitted_at":"2026-04-23T07:52:16Z","abstract_excerpt":"Temporal metamaterials, created by modulating the refractive index in time, offer powerful means of controlling wave propagation but still lack a systematic design methodology. Here, we develop an analytic inverse-design framework rooted in space-time duality and the established theory of one-dimensional spatial inverse scattering. By prescribing reflection (backward-wave) and transmission (forward-wave) responses in rational-function form, we obtain closed-form refractive-index modulations that are guaranteed to be physically admissible. This approach avoids iterative optimization and provide"},"claims":{"count":4,"items":[{"kind":"strongest_claim","text":"By prescribing reflection (backward-wave) and transmission (forward-wave) responses in rational-function form, we obtain closed-form refractive-index modulations that are guaranteed to be physically admissible.","source":"verdict.strongest_claim","status":"machine_extracted","claim_id":"C1","attestation":"unclaimed"},{"kind":"weakest_assumption","text":"That space-time duality permits a direct, lossless transfer of one-dimensional spatial inverse scattering solutions to the temporal modulation domain without introducing unphysical artifacts or requiring additional constraints.","source":"verdict.weakest_assumption","status":"machine_extracted","claim_id":"C2","attestation":"unclaimed"},{"kind":"one_line_summary","text":"An analytic inverse-design framework for temporal metamaterials yields closed-form refractive-index modulations from prescribed rational reflection and transmission responses by leveraging space-time duality and one-dimensional spatial inverse scattering theory.","source":"verdict.one_line_summary","status":"machine_extracted","claim_id":"C3","attestation":"unclaimed"},{"kind":"headline","text":"Prescribing rational reflection and transmission responses produces closed-form time-varying refractive index profiles for temporal metamaterials.","source":"verdict.pith_extraction.headline","status":"machine_extracted","claim_id":"C4","attestation":"unclaimed"}],"snapshot_sha256":"ad78082d0347d7657952efa078102146d9642a0fe5e9d1e67cf9204b66116905"},"source":{"id":"2604.21383","kind":"arxiv","version":1},"verdict":{"id":"58e0a955-55f7-4e4c-945e-3e296af8f594","model_set":{"reader":"grok-4.3"},"created_at":"2026-05-09T21:08:50.217140Z","strongest_claim":"By prescribing reflection (backward-wave) and transmission (forward-wave) responses in rational-function form, we obtain closed-form refractive-index modulations that are guaranteed to be physically admissible.","one_line_summary":"An analytic inverse-design framework for temporal metamaterials yields closed-form refractive-index modulations from prescribed rational reflection and transmission responses by leveraging space-time duality and one-dimensional spatial inverse scattering theory.","pipeline_version":"pith-pipeline@v0.9.0","weakest_assumption":"That space-time duality permits a direct, lossless transfer of one-dimensional spatial inverse scattering solutions to the temporal modulation domain without introducing unphysical artifacts or requiring additional constraints.","pith_extraction_headline":"Prescribing rational reflection and transmission responses produces closed-form time-varying refractive index profiles for temporal metamaterials."},"integrity":{"clean":true,"summary":{"advisory":0,"critical":0,"by_detector":{},"informational":0},"endpoint":"/pith/2604.21383/integrity.json","findings":[],"available":true,"detectors_run":[{"name":"doi_compliance","ran_at":"2026-05-20T01:05:40.362008Z","status":"completed","version":"1.0.0","findings_count":0}],"snapshot_sha256":"fe58527185d3af7998909aa00b84687307de3e4d6e8cdcf170c68ae49c101e1e"},"references":{"count":33,"sample":[{"doi":"","year":1958,"title":"F. 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